Jawapan kertas 2Peperiksaan percubaan spm sains kertas 2

SMK Derma

No Rubrik markah1(a)

Blood group

A B AB O

Number of students

6 7 2 15

1

(b)HISTOGRAM 2

(c )

√

1

2(a)Temperature decreases No change in

temperatureTemperature increases

√

1

(b) 34.5 0C 1

(c ) (i) Manipulated variable: volume of water(ii) Responding variable: temperature change//final temperature

11

(d) Different substance when added with water produce different final temperature/temperature change

1

2(a)

Type of rubberJenis getah

Initial length rubber

Panjang awal jalur getah

(cm)

Length of rubber after weight is hung

Panjang jalur getah apabila digantung pemberat (cm)

Vulcanised rubberGetah

tervulkan

7 ..8.0..

Natural rubberGetah asli 7 ..9.0..

(b) Vulcanised rubber is more elastic than natural rubber 1(c) Mass of weight 1(d) Vulcanised rubber is a type of rubber that produce less elongation after weight is

removed1

4 (a) 8/0.2 = 40 cm/s 1

(b) Velocity increases//the trolley accelerate 1(c) (i) the no of trolley 1

((ii) different inclination of the track(iii)velocity of the trolley

(d)

Section B5 (a) X:neutron

Y: radioactive radiation(b) Nuclear energy(c) 1.kills body cells

2.causes mutation//burns the skin/causes cancer(d) i. Medicine:cobalt-60 used to treat cancer

ii. agriculture:carbon-14 used to determine the usage of carbon during photosyntesis

6 (a) 5 metre 1

(b)1

(b) Virtual( maya)Sonsang sisi,//jarak ojek sama dengan jarak imej// size objek sama dengan size imej

7 (a)global warming/green house effect(b) carbon dioxide/carbon monoxide(c) the global temperature increases/increase sea level//ice berg in the pole melt faster(d)plants absorb carbon dioxide to carry photosyntesis process The concentration of carbon dioxide gas decreases

8 (a) Saponification(b) (i) sodium chloride(iii) To precipitate the soap//reduce the solubility of soap(c) produce foam when shake with water//feel slippery when touch

(d)

(e)Sodium hydroxide/potassium hydroxide

9 (a)(i) to keep food last longer//reduce food spoilage

(ii) sugar/salt/vinegar/sodium nitrite//sulphur dioxide//benzoic acid(b) mannitol/sorbitol/xylitol(c) biscuit will turn rancid(tengik)(d)lecithin /gelatin

10 (a)When the mass of an object increases, the time taken to stop of moving object increases//when the mass of an abject increase, the inertia of the object increases(b) to study the realtionship between mass of the object and inertia/ the time taken to stop the swinging object

(ii) Manipulate variable:mass of objectResponding variable: the time taken to stop swinging objectConstant variable: size of pail//length of stringList of apparatus:two pails with same size,sand,rope,hanging place,stopwatch

(vi) Procedure:1. Hang the 500g load to the retort stand.2. Swing the load and state the time until the load

stops swinging.3. Repeat steps 1 and 2 for 100 g load

(v)Mass of load(g) Oscillation period

0/500100

(vi) Hypothesis is accepted // if the mass of the load increases, the oscillation period also increases.// other suitable hypothesis.

11(a) the atom in pure atom is same size and arrange in orderly manner

and closly packedmalleable and ductile

(b)(i) Each alloy is made of two or more elements. Alloys are harder//Alloy are malleable//all;oys are more resistance to corrosion than its pure metals. (ii)Piuter/duralumin/brass Carbon/plumpum/ any metal/plastic Reason: because it is made up of one element. (iv)an alloy is a materials which is made up of two or more elements and it is harder than its pure metal

1 + 1

1 + 1

11

1111

12 (a) use mordern technologyuse quaality breedsoptimum use of land and irrigated areasefficient land managementresearch and develpomenteducation and guidance for farmers(any four answers)(b)Aim:to choose the most suitable menu for a child who is at the growing stageExplanation:Menu 1: contains high content of fats and carbohydrates that provides energy for the childMenu 2: contains carbohydrates that provide energy for the child and proteins for growing . fibre can prevent constipation.Menu 3:contains high fibre and carbohydrates.Priority:Menu 2 will be the first choice, followed by menu 3 and menu 1Reason:Menu 2 contains proteins that is necessary for a growing child.Menu 3 contains too much sugar that will cause obesity.Menu 1 contains contains high content of fats and chlosterol which will also cause obesity.

1111(any 4)

1

1

1

1

1

1(any one)